TWI518004B - Ship - Google Patents

Description

Ship

The invention relates to ships, and in particular to ships having a plurality of cargo holds.

A ship having a plurality of cargo holds, such as a bulk carrier, is a ship that mainly transports bulk cargo such as grain, coal, iron ore, cement, etc. of wheat. In the ship, it is often idling in one way and becomes a ballast voyage. Therefore, in a bulk carrier or the like, there is generally a ballast water tank as described in Patent Document 1. Patent Document 1 describes a hull structure of a bulk carrier having a double bottom tank, a waste water tank and a shoulder tank, and the double bottom tank, the waste water tank and the shoulder tank are used as ballast water tanks to make ballast water (sea water) pairs These ballast tanks are flooded.

Normally, at light loads, only the ballast tanks sail underwater. However, the volume of the ballast tank is set such that the bottom of the bow and the propeller are sufficiently submerged in the water in a state where the waves are not large. Therefore, there are cases where the bow bottom and the propeller are exposed from the sea surface during the stormy weather due to the hull shaking or the difference in the waves.

On the other hand, in the stormy weather, the bottom of the bow and the propeller are exposed from the sea surface due to the hull shaking, and the damage caused by the engine idling or impact may occur. Therefore, during stormy days, the increase in ballast water allows the hull to sink deeper. At this time, since the volume of the ballast tank is insufficient, as described in Patent Document 2, the ballast water is also introduced into the water in the specific cargo tank. Hereinafter, the cargo hold of both the loaded cargo and the ballast water is referred to as a "ballasted cargo hold".

[Advanced technical literature]

[Patent Document 1] JP-A-9-301266

[Patent Document 2] JP-A-63-166687

In recent years, in order to improve the efficiency of cargo handling, it has begun to build bulk carriers that are still reducing the total capacity of the cargo hold. In the ship, the average volume of one cargo hold becomes larger. Therefore, the ballast amount of the water in the ballast and the cargo tank becomes excessively large, and the following problems occur.

(1) It takes a lot of time to fully load the dedicated ballast tank 22 with ballast water, so the power consumption of the ballast water pump or the ballast water treatment device also increases. In addition, in the case of being predicted to sail in stormy weather, it is necessary to start water intake early. This is because the ballast water caused by the hull is shaken when the ballast water is not fully loaded, and the ballast water is shaken by the hull, and the restorability is lowered or the hull is damaged.

(2) Since the hull exceeds the necessary weight, the speed of the ship is lowered, and the sailing schedule is delayed, or energy such as fuel is additionally required, and the efficiency is lowered. Moreover, in the case where the ballast-capable cargo tank is started to enter the water early, the navigation time in the state where the weight of the hull is increased becomes longer, and the efficiency becomes worse.

(3) In the case of loading cargo in a ballasted cargo tank that allows ballast water (seawater) to enter the water, in order to prevent corrosion of the hull or cargo caused by residual seawater, it is necessary to wash the ballast and cargo tank with clean water. The larger the ballast and cargo tank is, the manpower or working hours are required for the washing operation, and the time required for loading is also lengthen.

(4) Since the amount of ballast water is too large, a greater bending moment is generated in the hull, so a stronger reinforcement is required, and the weight of the hull is increased. The increase in the weight of the hull is a cause of a decrease in the speed of the ship or an increase in fuel, causing a deterioration in efficiency.

(5) Because the cargo compartment is generally required to be airtight, the ballast and cargo tank is not provided with an air supply and exhaust port provided for air in and out of the normal ballast water tank. Therefore, in order to increase the air in the ballast, the vent door of the hatch cover must be opened and the manpower operation is required. Moreover, in the case where the operation is forgotten, there is a possibility that damage occurs on the door cover or the inner wall.

The present invention has been made in view of the above problems, and an object thereof is to provide a ship that does not become excessively large even when it is lightly loaded or in a stormy weather.

According to the present invention, there is provided a ship comprising a plurality of cargo holds, characterized in that the cargo hold is distinguished as a dedicated cargo hold for loading only cargo, and a dedicated ballast tank with only ballast water being fed.

The dedicated ballast tank is configured to meet the heavy ballast conditions that may be required by the class rules. Further, the dedicated ballast tank is disposed, for example, at a position including a floating center of the ship in a state where the ballast water is fully loaded, or a position at which the adjacent dedicated cargo tank includes the floating center. Further, the dedicated ballast compartment may be formed such that the length in the longitudinal direction of the hull is shorter than the length in the longitudinal direction of the hull of the dedicated cargo hold.

The special ballast tank can also be supplied with gas for supply and discharge. exhaust vent.

The dedicated ballast tank may also be disposed in the cargo hold of the existing ship to be removed from the cargo hold disposed at the central portion, and the dedicated auxiliary storage bin is disposed between the dedicated ballast tank and the dedicated cargo hold. Further, the dedicated ballast compartment may be disposed at a position where the cargo compartment disposed at the center portion and the cargo compartment adjacent thereto are removed.

According to the above-described ship of the present invention, by configuring a dedicated ballast tank, the appropriate ballast amount required at light load or stormy weather can be set according to the size or weight of the ship, and the ballast amount can be made. Not too big.

Hereinafter, embodiments of the present invention will be described using Figs. 1 to 3 . Here, FIG. 1A to FIG. 1D are diagrams showing an example of a ship according to the first embodiment of the present invention, and FIG. 1A is an overall configuration diagram when transporting goods, and FIG. 1B is an overall configuration in a stormy weather. 1C is a CC cross-sectional view of FIG. 1B, and FIG. 1D is a DD cross-sectional view of FIG. 1B. 2A to 2D are diagrams showing an example of a ship of the prior art, 2A is an overall configuration diagram when transporting goods, and 2B is an overall composition diagram at stormy weather, 2C In the CC cross-sectional view of Fig. 2B, the second DD is the DD cross-sectional view of Fig. 2B.

As shown in Figs. 1A to 1D, the ship 1 according to the first embodiment of the present invention is a ship having a plurality of cargo holds 2, and the cargo hold 2 is distinguished from a dedicated cargo hold 21 in which only cargo is loaded, and only ballast water is used. Special ballast tank for water intake twenty two.

The ship 1 is, for example, a bulk cargo ship, and is a ship mainly transporting bulk goods such as grain of wheat, coal, iron ore, cement, and the like. Further, although not shown, the ship 1 is a cargo handling equipment for bulk cargo, and may also have a deck crane. Further, although not shown, the ship 1 is used as a ballast water tank, and any of the shoulder tank, the double bottom tank, and the waste water tank may be omitted, or a ballast of another shape such as a double hull side tank may be used. Water tank. Furthermore, the ship 1 can also have a so-called double-shell (double hull shell) construction.

The conventional ship 10 shown in FIGS. 2A to 2D shows an example of a bulk carrier similar to the ship 1. The conventional ship 10 has a plurality of cargo holds 20 as shown in Fig. 2A. Generally, the cargo hold at the center portion constitutes the ballast and cargo hold 202, and the remaining cargo hold constitutes a dedicated cargo hold 201 for loading only the cargo. Further, in general, in the conventional ship 10, the dedicated cargo hold 201 and the ballast-capable cargo hold 202 have substantially the same shape, and have substantially the same length Lp in the longitudinal direction of the hull.

Further, as shown in Fig. 2C, the ship 10 has a double bottom tank 101, a waste water tank 102, and a shoulder tank 103, which constitute a ballast water tank into which ballast water is injected or discharged. Further, as shown in Fig. 2A, the ballast water pump 105 is installed in the engine room 104 of the ship 10, and supplies the ballast water (sea water) from the bottom of the ship to the double bottom tank 101, the waste water tank 102, the shoulder tank 103, and the ballast. The ballast water piping 106 of the cargo tank 202 is also connected to the ballast water pump 105.

On the other hand, in the case of transporting the goods of the bulk cargo, as shown in Fig. 2A, for example, the ship 10 sails in a state where the desired bulk cargo is loaded in all of the special cargo hold 201 and the ballast cargo hold 202. In this state, because the ship The weight of 10 is sufficiently large, so the draught of the ship 10 is deep, and even in the case of stormy weather, the possibility that the propeller 107 is exposed to the sea surface is low.

Further, in the case of a idling load before the loading of the bulk cargo or a light load with a small load of the cargo, and predicting the weather in a stormy weather, as shown in FIG. 2B, in the state in which the ballast water tank 202 is fully loaded with the ballast water, Ship 10 sailing. At this time, as shown in Figs. 2C and 2D, the ballast water of each of the ballast tanks of the double bottom tank 101, the waste water tank 102, and the shoulder tank 103 is also flooded.

On the other hand, the ship 1 of the present embodiment has a double bottom tank 11, a waste water tank 12, a shoulder compartment 13, an engine room 14, a ballast water pump 15, a ballast water pipe 16, and a propeller 17, like the conventional ship 10. However, instead of the ballast dual cargo hold 202, there is a dedicated ballast tank 22.

The special ballast tank 22 is not loaded with the required bulk cargo, but only the tank containing the ballast water, although similar in construction to the ballast tank 202, it is constructed to withstand pressure because it does not carry bulk cargo. The structure of the strength of the state in which the water is fully loaded can be Moreover, the size (capacity) and position of the dedicated ballast tank 22 are designed to prevent damage caused by engine idling or impacting due to the hull of the stormy weather and the propeller 17 or the bow bottom being exposed from the sea surface. Specifically, the dedicated ballast tank 22 is designed to meet the heavy ballast conditions that may be required in accordance with the class rules (eg, the steel ship rules CSR-B 2010 edition, Chapter 4, Section 7, 2.2) in stormy weather. Configuration is formed. Here, in the ship 1, the heavy ballast state which may be required according to the class rules means a state in which the following conditions are satisfied, for example, in a state where the cargo is not loaded.

(1) Assume that the ballast tank is fully loaded, partially loaded or unloaded. In addition, in Ballast tanks are partially loaded and must meet the conditions for shear and bending moments in Section 3 of Chapter 4 of the Code.

(2) The dedicated ballast tank 22 is filled with ballast water.

(3) Set the propeller water rate I/D to be 60% or more. Here, I is the distance from the center line of the propeller to the water line (drink), and D is the diameter of the propeller.

(4) As the stern is poor. However, the difference in draught should not exceed 1.5% of the length L _BP between the vertical lines. In addition, the difference in draught means the inclination of the ship in the front and rear direction, that is, the difference between the draft of the bow and the draught of the stern. The difference between the stern and the draft is that the stern draught is deeper than the draft.

(5) The draft at the bow is 3% or more of the length L _BP between the vertical lines. However, it does not have to exceed 8m.

By satisfying the heavy ballast state in stormy weather, it is possible to suppress the damage caused by the engine being idling or hitting due to the hull being shaken and the propeller 17 or the bow bottom being exposed from the sea surface. In addition, the heavy ballast state required by the above-mentioned classification rules is only an example of the heavy ballast state, and the "heavy ballast state" means that the ballast water is loaded to the propeller 17 or the bow of the ship without being shaken by the hull. The state exposed from the sea. Further, for example, a ship that does not require a heavy ballast state in a stormy weather like a domestic ship does not need to determine the size (capacity) or position of the dedicated ballast tank 22 based on the heavy ballast state, and can also be used as a general pressure. The alternative to the water tank determines the size (capacity) or location of the dedicated ballast tank 22.

The length Lp of the hull length direction of the ballast cargo tank 202 of the conventional ship 10 tends to become longer in recent years, and the capacity of the ballast cargo compartment 202 also increases. In contrast, the ballast required to meet the heavy ballast state The quantity system is generally less than the capacity of the ballast dual cargo hold 202 having a length Lp. For example, in the case of a ship 10 of several tens of thousands of tons, the ballast amount required to satisfy the heavy ballast state is also satisfied with the capacity of 1/2 to 1/4 of the ballast tank 202.

Here, as shown in FIG. 1A, the length of the hull length direction of the dedicated cargo hold 21 is Lc, and the length of the hull length direction of the dedicated ballast tank 22 is Lt. As described above, the amount of ballast required to satisfy the heavy ballast state is smaller than that of the conventional ballast tank 202. Further, as shown in FIG. 1C and FIG. 1D, since the cross-sectional area of the dedicated ballast tank 22 has substantially the same size as the cross-sectional area of the dedicated cargo tank 21, in order to reduce the capacity of the dedicated ballast tank 22, it is only necessary to make the capacity of the dedicated ballast tank 22 small. The length Lt of the hull length direction can be shortened. Therefore, the dedicated ballast tank 22 is formed such that the length Lt in the longitudinal direction of the hull is shorter than the length Lc of the hull length direction of the dedicated cargo hold 21.

Further, the length Lc of the hull length direction of the dedicated cargo hold 21 is set to the length Lt of the hull length direction of the dedicated ballast tank 22, and the remaining space may be divided by the number to be set. The dedicated ballast tank 22 is disposed, for example, as shown in FIG. 1B, and is disposed at a position including the floating center B of the ship 1 in a state where the ballast water is fully loaded. Generally, since the floating center B is located at the center portion of the longitudinal direction of the ship 1, the dedicated ballast tank 22 is also disposed at the center portion of the longitudinal direction of the ship 1. In this manner, by arranging the dedicated ballast tank 22 at a position including the center of buoyancy B, the ship 1 in a state where the ballast water is fully loaded can be effectively stabilized, and the heavy ballast state can be easily maintained. Further, in the case where the water in the stern is poor, the position of the floating center B is slightly biased toward the stern side from the center portion of the length L _BP between the vertical lines.

Further, in the case where the dedicated ballast tank 22 cannot be placed at a position where the center of gravity B is included due to other restrictions, the adjacent dedicated cargo hold 21 is placed at the position including the floating center B, and the ballast tank is adjusted. The amount of water inflow is used to adjust the center of gravity of the vessel 1 to ensure the required draught and posture.

Therefore, as shown in FIG. 1A, in the case where four dedicated cargo holds 21 are to be installed in the ship 1, two dedicated cargo holds 21 are disposed in front of and behind the dedicated ballast tank 22. At this time, depending on the configuration of the dedicated ballast tank 22, the lengths of the spaces before and after the dedicated ballast tank 22 may be different. In this case, it is only necessary to divide the number of the dedicated cargo bays 21 in each space.

Here, the case where four dedicated cargo holds 21 are provided will be described. However, in the case where five dedicated cargo holds 21 are to be provided, it is only necessary to form two dedicated cargo holds 21 and three dedicated cargo holds 21 via the dedicated ballast tanks 22. Further, in the case where it is desired to provide six or more dedicated cargo holds 21, it is also possible to allocate the dedicated cargo hold 21 via the dedicated ballast tank 22 in accordance with the same idea.

Further, the dedicated cargo hold 21 basically constitutes the same configuration as the conventional dedicated cargo hold 201, but since it is only loaded with the desired bulk cargo, it is not necessary to be a ballast-use cargo hold. Therefore, the dedicated cargo hold 21 does not have to have a structure or equipment such that the ballast water rises and drains, and an air supply port or the like that allows air to enter and exit when the ballast water rises and drains.

Further, since the dedicated ballast tank 22 only loads the water into the water and does not load the cargo, the airtightness of the special cargo compartment 21 is not required. Therefore, the dedicated ballast tank 22 can also have an air supply and exhaust port 18 for supplying and discharging gas. The air supply and exhaust port 18 may be a simple communication port or opening that communicates the inside and the outside of the dedicated ballast tank 22, and may have an opening and closing means such as a valve. Especially, in design In the case of the normally open supply and exhaust port 18, the operation for adjusting the pressure in the tank when the dedicated ballast tank 22 is up-drained is not required, and the damage of the dedicated ballast tank 22 can be easily suppressed.

Next, a ship 1 according to another embodiment of the present invention will be described. Here, FIG. 3A and FIG. 3B show a ship according to another embodiment of the present invention, and FIG. 3A shows a second embodiment, and FIG. 3B shows a third embodiment. In the respective drawings, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.

The ship 1 system shown in Figs. 3A and 3B is assumed to be modified from an existing ship. Now, consider the case where the conventional ship 10 shown in Figs. 2A to 2D is converted into the ship 1 of the embodiment of the invention.

In the second embodiment shown in Fig. 3A, the dedicated ballast tank 22 is placed in the cargo hold 20 (dedicated cargo hold 201 and ballast cargo hold 202) of the existing ship (ship 10), and the pressure placed at the center is removed. The position of the cargo hold 202 is used in combination, and the dedicated auxiliary storage bin 23 is disposed between the dedicated ballast tank 22 and the dedicated cargo hold 201.

Since the length Lp in the longitudinal direction of the hull of the cargo hold 20 of the conventional ship 10 is longer than the length Lt of the hull length direction of the dedicated ballast tank 22, the ballast cargo tank 202 disposed at the center portion is removed. It is easy to ensure the space for configuring the dedicated ballast tank 22. Further, since the floating center B of the ship 1 in the state in which the ballast water is fully loaded in the dedicated ballast tank 22 is generally located at the substantially central portion of the hull, the cargo hold 20 disposed at the center portion is removed (here, ballast) In combination with the cargo hold 202), the dedicated ballast tank 22 can be placed at a position that will include the center of buoyancy B.

The dedicated auxiliary storage bin 23 is disposed in the remaining space after the ballast-cum-cum-in cargo tank 202 is removed and the dedicated ballast tank 22 is disposed, that is, the difference between the length Lp of the length direction of the hull and the length Lt of the hull length direction. The cargo space of the space 2. Since the dedicated auxiliary storage compartment 23 is additionally added, the length La in the longitudinal direction of the hull may be shorter than the length Lt of the hull length direction of the dedicated ballast compartment 22. Further, the dedicated auxiliary cargo compartment 23 basically has substantially the same structure as the dedicated cargo hold 21 except that the length La in the longitudinal direction of the hull is shorter than the length Lc of the hull length direction of the dedicated cargo hold 21.

In the third embodiment shown in Fig. 3B, the dedicated ballast tank 22 is placed in the cargo tank 20 (dedicated cargo tank 201 and ballast cargo tank 202) of the existing ship (ship 10), and the pressure placed at the center is removed. The position of the cargo hold 202 and the dedicated cargo hold 201 adjacent thereto is carried out, and the dedicated auxiliary storage bin 23 is disposed between the dedicated ballast tank 22 and the dedicated cargo hold 21 (201).

By removing the two cargo compartments 20 in the conventional ship 10, a space wider than that of the second embodiment can be secured. Therefore, it is possible to ensure that the remaining space after being disposed in the dedicated ballast tank 22 is wide, and the size of the dedicated auxiliary cargo compartment 23 can be made larger than that of the second embodiment. This third embodiment is effective when the dedicated auxiliary storage bin 23 of the second embodiment is small and difficult to use.

Further, although not shown, for example, all of the cargo holds 20 (dedicated cargo hold 201 and ballast cargo hold 202) may be removed, and the cargo hold 2 (dedicated cargo hold 21 and dedicated ballast tank 22) of the embodiment of the cost may be changed. The cargo hold 2 (the dedicated cargo hold 21 and the dedicated ballast compartment 22) of the embodiment of the present embodiment is replaced by removing all of the cargo compartments 20 that are more forward or rearward than the cargo hold 20 (ballasted cargo hold 202) in the center.

According to the ship 1 according to the first to third embodiments, by arranging the dedicated ballast tank 22 for the new ship or the existing ship, it is possible to set the appropriate time in the storm weather depending on the size or weight of the ship 1. The amount of ballast can be made, and the amount of ballast can not be too large. As a result, the following effects are also obtained.

(1) It can shorten the time when the special ballast tank 22 is fully loaded with ballast water. Even if it is predicted to sail in stormy weather, the start of the water inlet time can be delayed, and the ballast water pump 15 or ballast water can be reduced. The power consumption of the processing device.

(2) Since the hull does not exceed the necessary weight, the reduction of the ship speed can be minimized, and the sailing time in the ballast state during storm weather can be optimized, and the delay of the navigation stroke can be suppressed, and The energy consumption of fuel and the like can be suppressed, and the efficiency can be improved.

(3) Since the cargo is not loaded in the dedicated ballast tank 22, it is not necessary to clean the dedicated ballast tank 22. Therefore, the work can be saved, and the time required for loading can be shortened.

(4) Since the ballast amount (the capacity of the dedicated ballast tank 22) is appropriately set, the bending moment in the ballast state during stormy weather can be suppressed to a minimum. Further, since the dedicated ballast compartment 22 in the center portion does not load the cargo, the bending moment at the time of loading the cargo can be alleviated. Therefore, the reinforcing member can be reduced, and the increase in the weight of the hull can be suppressed.

(5) The supply and exhaust port 18 can be installed in the dedicated ballast tank 22, and the work at the time of rising drainage can be facilitated, and the safety can be improved.

The present invention is not limited to the above-described embodiments, and can be applied to a ship having a plurality of cargo holds 2 (for example, a multipurpose cargo ship, a tanker, etc.), By appropriately changing the shape of the hull or the shape of the dedicated cargo hold 21, it is possible to absorb the load of the cargo of 22 parts of the dedicated ballast tank, and the like, and it is a matter of course that various modifications can be made without departing from the spirit and scope of the invention.

1‧‧‧ ship

2‧‧‧ cargo hold

18‧‧‧Exhaust vents

21‧‧‧Special cargo hold

22‧‧‧Special ballast tank

23‧‧‧Special auxiliary cargo hold

Fig. 1A is a view showing an example of a ship according to a first embodiment of the present invention, and is an overall configuration diagram when a cargo is transported.

Figure 1B is a diagram showing the overall composition of the ship shown in Figure 1A during stormy weather.

Fig. 1C is a cross-sectional view taken along line C-C of Fig. 1B.

Fig. 1D is a cross-sectional view taken along line D-D of Fig. 1B.

Fig. 2A is a view showing an example of a ship of the prior art, which is an overall configuration diagram when transporting goods.

Figure 2B is a diagram showing the overall composition of the ship shown in Figure 2A during stormy weather.

Fig. 2C is a cross-sectional view taken along line C-C of Fig. 2B.

The 2D drawing is a D-D sectional view of Fig. 2B.

Fig. 3A is a view showing a ship according to a second embodiment of the present invention.

Fig. 3B is a view showing a ship according to a third embodiment of the present invention.

1‧‧‧ ship

2‧‧‧ cargo hold

14‧‧‧ engine room

15‧‧‧ ballast water pump

16‧‧‧Ballast water piping

17‧‧‧propeller

18‧‧‧Exhaust vents

21‧‧‧Special cargo hold

22‧‧‧Special ballast tank

Lc‧‧‧ Length of hull length direction of special cargo hold 21

Lt‧‧‧ Length of hull length direction of special ballast tank 22

L _BP ‧‧‧Drop length

Claims (6)

A ship comprising a plurality of cargo holds, characterized in that the cargo hold is distinguished in the longitudinal direction of the ship as a special cargo hold for loading only cargo, and a special ballast tank with only ballast water being fed into the water; The ballast tank is disposed at a position including the floating center of the ship or at a position including a bow end direction and a center of the port side direction. A vessel as claimed in claim 1 wherein the dedicated ballast tank is configured to meet the heavy ballast conditions that may be required by the class rules. For example, in the vessel of claim 1, the dedicated ballast compartment is formed such that the length in the longitudinal direction of the hull is shorter than the length in the longitudinal direction of the hull of the special cargo hold. The vessel of claim 1, wherein the dedicated ballast compartment has an air supply and exhaust port for supplying and discharging gas. The vessel of claim 1, wherein the special ballast tank is disposed at a position where the cargo compartment disposed at the central portion of the cargo tank of the existing ship is removed, and the dedicated auxiliary warehouse is disposed at the special purpose Between the ballast tank and the special cargo hold. The ship of claim 5, wherein the special ballast tank is disposed at a position where the cargo hold disposed at the central portion and the cargo hold adjacent thereto are removed.